Preparation of addition products of fatty acid compounds with phenol aldehyde condensation products



United States Patent PREPARATEUN Gi ADBETIGN PRQDUQIS (1F FATTY AQID CQF/EPGUNDS Willi FPHENGL Ali- DEHYDE CGNDENSA'IEQN PR$DUCFTS Thomas J. Mcllaughtan, Sheboygan, Wis, assign-or to The Borden Company, New York, Nfih, a corporation at New Jersey No Drawing. Filed Aug. 3, 1959, Ser. No. 831,612

8 Claims. (Cl. 26il19) This invention relates to the controlled but rapid condensation of aqueous formaldehyde with a phenol and the combination of the product with a drying oil or other olefinic compound.

This application is a continuation-in-part of my copending application Serial No. 512,579, filed June 1, 1955, now abandoned.

The invention provides a process by which formaldehyde can be introduced into very hot phenol without violent initial reaction and with removal of a moderating agent as the formaldehyde becomes spent and retarding of the rate of condensation is no longer advantageous.

It provides also reaction products of drying oils and like unsaturated compounds with phenol aldehyde condensates of high speed of drying to tack-free condition.

I now reduce the time of drying such products to half or less that previously required for comparable materials, in some cases even from a day or so to 2 hours or less. This I accomplish by coupling the fatty acid component to the phenol aldehyde condensate predominantly at the para positions in the phenol nuclei of the said product.

My new products may be represented in general by the type formula 011 0 H O0 HFOC H2- I. R R n in which R is the added unsaturated compound and n represents and integral number, as within the range 1-20.

When the unsaturated compound is linoleic acid, for

example, then R becomes C H COOH. The nature of the union to an aryl group may be represented in part as follows:

CuHaiCOOH Here the bonding, to the para carbons of the phenol nuclei, I

is considered to involve opening of one carbon-to-carbon double bond of the acid.

Drying fatty oils are particularly satisfactory as the unsaturated compounds to be added.

When 'I first attempted, however, to use addition prodnets of such drying oils with the condensation products of phenol and formaldehyde, as the vehiclein varnishes and paints, I found the drying times objectionably long. I then made special phenol aldehyde condensation prodnets in which the para position was predominantly (60% or more) unreacted, i.e., free for acceptance of the fatty acid compounds. When I combined these products with drying fatty acid compounds, I obtained satisfactory drying rates.

Briefly stated, the invention comprises the herein described process of and product resulting from introducing formaldehyde in aqueous solution in small increments or continuously into phenol preheated to a temperature above the boiling point of water and in contact with an alkaline catalyst of condensation with the formaldehyde. As a result, the water of dilution of the formaldehyde, as introduced moderates the condensation at the start. Then, as the formaldehyde becomes largely reacted, the water hlhfiih Patented Got. 29, 1%63 ice will have been evaporated or distilled away, so that condensation of remaining formaldehyde with phenol is ac- As to materials, the phenol selected is any one of those 1 commonly used commercially in effecting condensation with an aldehyde with the exception of phenols which are substituted in the para position. Examples of such phenols that may be used are phenol itself C I-l OI-I, oand m-cresol, and 1,3,5-xylenol. Commercial cresylic acid is another example. Metaresorcinol is also operative in combining with the fatty acid compounds but is not recommended for use in making my products for use in paints and varnishes.

Formaldehyde is the aldehyde ordinarily used. -It is introduced in any commercial aqueous solution, as, for instance, in 37% formalin solution.

As catalyst in the condensation of the selected phenol with the aldehyde I use one of the conventional materials as, for example, sodium or potassium hydroxide or carbonate or calcium hydroxide. Acid catalyst such as hydrochloric, sulfuric or acetic are not entirely satisfactory. Under some conditions, the formic acid content of the commercial source of formaldehyde is sufiicient, however, to provide the desired catalytic eifect.

The proportion of catalyst is kept low, as within the range 0.02%5% of the weight of the phenol. The proportion used, within this range, is smaller when the alkali is strong.

The condensation is effected with the removal of water as introduced and as formed, this step causing a gradual rise in the temperature of boiling of the reacting mixture up to a final temperature of at least -160 C. I keep the temperature at all times during the introduction of the aqueous aldehyde above the boiling point of water but below that of the selected phenol under the prevailing conditions. Speed of drying to the tack-free condition of my product is promoted when the final temperature of the condensation reaction is raised to about 200 C; For best results, in the condensation, the phenol and catalyst mixture is preheated to 130 C. or higher, the formaldehyde added in increments, either streamwise or at close intervals of time at such rate that the temperature of reaction never falls below 130, and the temperature is maintained at least that high, by external heat if necessary, until the reaction is completed.

When substantially no more water is given off on further heating at the selected temperature, the reaction is considered complete, the heating to efiect condensation is then discontinued and the Whole is cooled. In the resulting condensation product, the para position on the nuclei is predominantly in unsubstituted and unreacted condition.

As the fatty acid component, to be added to the phenol and aldehyde condensation product made as described, I use an organic acid compound containing at least tWo carbon-to-carbon double bonds in the fatty acid therein. Examples of such compounds that I'use are the doubly unsaturated organic acids containing at least l6l9 carbon atoms to the molecule, commercial and satisfactory examples of which are linoleic, linolenic, a'bietic and the mixed fatty acids derived from the oil of soybean, linseed, China Wood, oiticica, and safilower.

Also I may use, as the fatty acid component, the amides of such organic acids or organic acid mixtures and esters of the acids with polyhydric alcohols, examples of which are glycerine, pentaerythritol, glycols, and the like. Examples of glycols that may be represented in the esters are ethylene, propylene and butylene glycol. Particularly satisfactory and economical results are obtained when the 3 esters are glycerides such as occur in nature in the form of the fatty drying oils containing two, three, or more double bonds to the molecule of a large part of the total higher fatty acids present, examples being linseed, perilla, oiticica, and dehydrated castor oils. The esters may be complete or partial, as illustrated by tri-, di-, or monoglycerides.

, Also, the acid component may be a mixture of organic acids containing at least two double bonds to the molecule with other carboxy acids of lower degree of unsaturation. Thus, I may use the doubly or more unsaturated compounds of kind described with admixed tall oil, cottonseed oil, or tallow foots. It will be understood that, with the use of such mixtures, some of the Rs in the formula first given above would represent the more unsaturated fatty acid and other Rs the less unsaturated. In any case, the proportion of the more unsaturated fatty acid compound must be adequate to assure the necessary drying properties. Also the R groups of the doubly unsaturated acids are relied upon to give the cross linkage with other Rs and thus to impart the desired resistance of the finished varnish or paint film to alkalies and solvents.

As the catalyst in combining the unsaturated fatty acid compound or component in the para positions of the phenol nuclei in the condensation product, I use cationic alkylation catalysts as, for instance, concentrated sulfuric acid, hydrogen chloride, aluminum chloride, stannic chloride, boron triiluoride or its common ethe'rate, and hydrofluoric acid. Sulfuric acid, the least expensive of these catalysts, is satisfactory and the one that I ordinarily use. When temperatures of around 200 C. or so are used in the reaction of the said condensation product with the organic acid compound, the alkylation catalyst may be omitted.

The addition of the organic acid compound to the said condensation product is effected under substantially anhydrous conditions. Water up to or so is permissible, particularly if the water is removed by volitilization as the reaction proceeds.

As to proportions of the organic acid compound to the phenol aldehyde condensation product, I select the proportion to fit the finished product to the use to which it is to be put. When the finished addition compound is to be utilized as the drying vehicle in a paint or varnish, I use 0.1-1 mole of the said acid compound for 1 mole of phenol represented in its condensation product with the aldehyde. The proportion which gives the best results under a Wide variety of conditions for the stated use is about 0.20.5 mole of the organic acid compound.

When the finished product is to be used as an additive to lubricant, then I reduce the proportion of the selected acid compound to approximately 0.01 to 0.1 mole to 1 mole of the phenol.

The proportion of the alltylation catalyst is the usual proportion commonly employed in olefin addition to aromatic nuclei as, for instance, 0.1%-3% of the catalyst on the weight of the phenol and aldehyde condensation product. 1% of the alkylation catalyst is satisfactory in most operations.

In general, I mix the phenol and aldehyde condensation product having the para position available for reaction, the selected organic acid, its ester or amide, and the alkylation catalyst. Then the mix is heated in a vessel with an outlet for escape of water present orginally in small amount or formed during the reaction. The heating is continued at a temperature above the boiling point of water and below the temperature of complete expulsion of the catalyst or boiling away of the selected phenol until the first stage reaction is substantially complete. Fractionation is used to advantage, so that materials other than water are returned to the vessel and steam is allowed to escape. The equipment is conventional in esterifications.

The first product is the combination of the acid compound through a carbon-to-carbon double bond with the benzene ring. Then the temperature is raised and the heating is continued until controlled cross linking is effected between the various Rs. This heating to cause cross linking is continued until the product comes to have the desired viscosity and dissolves to give a clear solution in benzene. The heating is discontinued before the product sets to a gel. Ordinarily I discontinue the second stage reaction when the viscosity of the product, as measured in a 50% solution in mineral spirits, shows a viscosity of about 50-1000 cps. For a varnish vehicle the heating is discontinued when the viscosity so measured is about 200 cps. For use as a core binder in foundry practice, the heating is continued until the viscosity in the 50% solution is about 800-1000 cps.

I obtain such results ordinarily when the complete heating cycle raises the final temperature to about 200 C. and the total time of heating is 1-10 hours. The longer times within this range are usable when it is desired to make the addition product one that after cooling is a hard, grinda-ble mass.

The invention will be further illustrated by description in connection with the following specific examples of the practice of it. In these examples and elsewhere herein proportions are expressed as part by weight unless stated specifically to the contrary.

Example 1 94 parts of anhydrous phenol (1 mole) and 0.1 part of calcium hydroxide as catalyst of condensation are mixed in a digester provided with a fractionating column. The mixture is brought to a boil. 57 parts of 37% formaldehyde solution in water (0.7 mole) are then introduced slowly so as not to lower the temperature at any time below C. The vapors are fractionated and condensed in equipment for drawing off and discarding water and returning other condensate to the digester, such equipment being conventional in elfecting other chemical reactions.

The heating and separation of Water are continued until the temperature of the reacting mass reached C. and substantially no more water separates at that tempera ture.

The product is the so-called A-stage res-in. It is thermoplastic. The para positions on the phenol nuclei in the condensation product are predominantly unreacted and therefore available for the addition reaction in the suc-- ceeding step.

The A-stage condensation product so made is cooled. Then linseed oil is admixed in amount corresponding to approximately 0.3 equivalent weight (0.1 mole as calculated on the basis of the saponification value). This requires 100 parts of the linseed oil. Into the mix there is incorporated 1 part of cationic alkylation catalyst, in this instance sulfuric acid. The whole is then heated until combination between the linseed oil and the phenol and formaldehyde condensation product has been carried to the stage at which the linkage of the oil to the condensation product has occurred. This heating covers a period of about 1 hour and the final temperature for this stage of the reaction is about 140 C.

Then the heating is continued, to raise the temperature finally to about 200 C. where the temperature is held for about 2 hours, i.e., until the product is soluble in benzene to give a clear solution and its viscosity is within the range 504000 cps, as measured cold in a 50% solution in mineral spirits, the exact stopping point being determined by the viscosity required in the use to which the product is to be put. In any case, the heating is discontinued before the product sets to a gel.

The material resulting from the addition of linseed oil to the phenol and formaldehyde condensation product and made as described in Example 1 is used as the vehicle, that is, film forming ingredient in varnish.

Example 2 100 parts of the A-stage condensation product of arcasve Example 1 are mixed with 80 parts of heat bodied linseed oil and 20 parts of China-Wood oil.

The resulting mixture is then cooked under a non-oxidizing atmosphere to the condition giving an 8-inch string test. parts additional of the A-stage product are then stirred in, to check further thickening.

The whole is then cooled and dissolved in an equal weight of mineral spirits. The particular sample of mineral spirits used here is one of kauri-butanol value at least 60.

To the solution of the addition product of the bodied linseed oil with the phenol formaldehyde condensation product in the mineral spirits, I add and mix in 0.1 part of lead naphthenate and 0.1 part of cobalt naphthenate, to serve as drying agents.

When the varnish so made is poured on test surfaces, the resulting film dries tack-free in 2 hours. It dries hard overnight.

By contrast, films made similarly but with phenol formaldehyde condensation product having the para positions predominantly reacted during the original condensation are not tack-free after 24 hours.

Example 3 The procedure of Example 1 is followed except that the phenol is replaced by an equimo'lecular weight of any of the other phenols disclosed herein and the final product is used in making a varnish as described in Example 2.

Example 4 The procedure of Example 1 is followed except that the linseed oil replaced by an equivalent weight (on the basis of fatty acid represented) of any of the other fatty acid compounds listed herein and the product is used in making a varnish as described in Example 2.

Example 5 100 parts of commercial cresylic acid and 60 parts of the commercial aqueous formalin solution were mixed and boiled in a digester provided with suitable fractionating column, condenser and water separator. The temperature was raised finally to 180-190 C. and the heating continued until the formaldehyde Was substantially all consumed.

Then 100 parts of linseed oil was added, the temperature was dropped to practically 130 C. and 1 part of boron trifluoride was added. Heating was continued at approximately 140 C. for 1 hour. The temperature was then raised over approximately 1 hour until 200 C. was reached.

Example 6 In a modification of the invention, some of the phenol nuclei in the phenol formaldehyde condensation product made as described in Example 1, for instance, are combiued at the para positions with an olefin hydrocarbon. In such a way there is prepared a resinous material in which para positions on the nuclei are occupied partly by drying oil acids and partly by olefinic hydrocarbons.

Example 7 In making this modified form of resin, I proceed as described above as in Examples 1-6 except for the following changes.

After the A-stage thermoplastic condensation product of the phenol and aldehyde has been made, I introduce an olefin hydrocarbon of which suitable examples are isobutylene, d-limonine, isoprene, butadiene, styrene, and butene. Better results, particularly as to less tack in the finished paint and varnsh films, are obtained when the olefinic hydrocarbon selected for use are symmetrically branched chains.

The olefin is introduced in proportion to combine with something less than half of the para positions in the phenol aldehyde condensation products and ordinarily about 0.2 to 0.4 of the total available para positions.

- The catalyst used with the hydrocarbon is any one of the alkylation catalysts given above. The reaction speed is so rapid that the olefin introduced into the mix is retained, even though the temperature of the mix is well above the boiling point of the hydrocarbon used. When the hydrocarbon has been introduced and combined, in the predetermined propontion, then the fatty acid compound, such as a drying oil, is added and the reaction completed in the manner described above.

The products so made with the addition of both the hydrocarbon and the fatty acid component are characterized by increased hydrocarbon solubility and also increased solubility in rubber, as compared to the addition product with no olefin hydrocarbon. At the same time, they are tough and hard.

In a modification of this example the fatty acid compound is omitted.

Example 8 A core binder is made of the following composition and by the steps shown:

Mix

Parts A-stage condensation product made as in Exaniplel Soya fatty acids 100 China-wood oil 10 Cook under inert gas to 8" string. Cut to 75% solids with mineral spirts of a 60 kauributanol value.

Mull 5 minutes.

The resulting cores give strength tests of 290 psi. after 15 minutes cure at 200 C.

Using standard foundry core oils, cores of only 10 psi. are obtained after 14 minutes cure at 200 C. and of 190 p.s.i. after 30 minutes cure.

Example 9 In making an additive for lubricating oil, the proce dure of Example 1 is followed except that the linseed oil is replaced by a semidrying oil, in this case soya bean oil, and the proportion of the oil is reduced to 0.05 mole for 1 of the phenol used.

The final product is then mixed with a petroleum lubricating oil in the proportion of 0.25% on the weight of the oil.

It will be understood that it is intended to cover all changes and modifications of the examples of the invention herein chosen for the purpose of illustration which do not constitute departures from the spirit and scope of the invention.

1 claim:

1. In making a phenol-aldehyde condensate in which the para position in the phenolic portion of the condensate is predominantly in unreacted condition, the process which comprises heating a mixture of a para-unsubstituted phenol in substantially anhydrous condition with an inorganic alkali catalyst of condensation of phenol with an aldehyde and in communication with the atmosphere to a temperature of at least C. and below the boiling point of the phenol, then introducing an aqueous solution of formaldehyde slowly into the preheated mixture in total proportion of 0.1-1 mole of the form-aldehyde for 1 mole of the phenol, and maintaining the resulting mixture at all times during the introduction of the formaldehyde at a temperature within the range stated and until all of the formaldehyde has been introduced and substantially no more water escapes from the mixture at the said temperature.

2. The process of claim 1 the said phenol being of the formula C l-l OH.

3. The process of claim 1, the said phenol being cresol.

4. The process of claim 1 which includes mixing the said condensation product with an organic acid compound in the proportion of 0.1-1 mole of said compound for 1 mole of phenol represented in the condensation product, the acid compound being selected from the group consisting of unsaturated higher fatty acids containing 16-19 carbon atoms and at least 2 carbon-to-carbon double bonds to the molecule, abietic acid, and the esters of said acids and acid with glycols, glycerine and pentaerythritol, heating the resulting mixture to a final temperature of about 200 C. until the viscosity of the resulting product comes to be at least 5'0 cps. as measured in a cold 50% solution in mineral spirits, and discontinuing the heating before the product sets to a gel.

5. The process of claim 4, the said organic acid compound being a fatty glyceride drying oil.

6. The process of claim 4, the said organic acid compound being linseed oil.

7. The process of claim 1 which includes mixing the said condensation product with an organic acid compound in the proportion of 0.1-1 mole of the said compound for 1 mole of phenol represented in the condensation product, the acid compound being selected from the group consisting of unsaturated higher fatty acids containing 16-19 carbon atoms and at least 2 carbomto-carbon double bonds to the molecule, abietic acid, and the esters of said acids and acid with glycols, glycerine and pentaerythri-tol, heating the resulting mixture to a final temperature of from about 140 C. to about 200 C. in contact with an acidic cationic catalyst of alkylation until the viscosity of the resulting product comes to be at least cps. as measured in a cold 50% solution in mineral spirits, and discontinuing the heating before the product sets to a gel.

8. The process of claim 7 the said catalyst being selected from the group consisting of sulfuric acid, hydrogen chloride, aluminum chloride, stannic chloride, boron trifluoride, boron trifluoride etherate, and hydrofluoric acid and the proportion of the said catalyst being about 0.1-3 parts for parts by weight of the said condensation product.

References Cited in the file of this patent UNITED STATES PATENTS 1,033,044 Aylsworth July 16, 1912 1,080,188 Wiechmann Dec. 2, 1913 1,271,392 Van Voorhout July 2, 1918 1,975,884 Weith Oct. 9, 1934 OTHER REFERENCES Ellis: The Chemistry of Synthetic Resins, Reinhold Pub. Co. (1935), pages 316-329, 344-8, 396-407. 

1. IN MAKING A PHENOL-ALDEHYDE CONDENSATE IN WHICH THE PARA POSITION IN THE PHENOLIC PORTION OF THE CONDENSATE IS PREDOMINANTLY IN UNREACTED CONDITION, THE PROCESS WHICH COMPRISES HEATING A MIXTURE OF A PARA-UNSUBSTITUTED PHENOL IN SUBSTANTIALLY ANHYDROUS CONDITION WITH AN INORGANIC ALKALI CATALYST OF CONDENSATION OF PHENOL WITH AN ALDEHYDE AND IN COMMUNICATION WITH THE ATMOSPHERE TO A TEMPERATURE OF AT LEAST 130*C. AND BELOW THE BOILING POINT OF THE PHENOL, THEN INTRODUCING AN AQUEOUS SOLUTION OF FORMALDEHYDE SLOWLY INTO THE PREHEATED MIXTURE IN TOTAL PROPORTION OF 0.1-1 MOLE OF THE FORMALDEHYDE FOR 1 MOLE OF THE PHENOL, AND MAINTAINING THE RESULTING MIXTURE AT ALL TIMES DURING THE INTRODUCTION OF THE FORMALDEHYDE AT A TEMPERATURE WITHIN THE RANGE STATED AND UNTIL ALL OF THE FORMALDEHYDE HAS BEEN INTRODUCED AND SUBSTANTIALLY NO MORE WATER ESCAPES FROM THE MIXTURE AT THE SAID TEMPERATURE. 